<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
    <h1>我是第二页</h1>
    <button id="link">回首页</button>
    <button id="play">play</button>
    <button id="pause">pause</button>
    <script>
        const link = document.getElementById('link');
        link.onclick = function(){
            window.history.back()
        }
        const btn1 = document.getElementById('play');
        btn1.onclick = function(){
            parent.document.getElementById('audio').play()
        }
        const btn2 = document.getElementById('pause');
        btn2.onclick = function(){
            parent.document.getElementById('audio').pause()
        }
    </script>
</body>
</html>